Fait mathématique: 16500 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Culture générale: 16500 is an uninteresting number.
Date historique: March 4th is the day in 1918 that the USS Cyclops (AC-4) departs from Barbados and is never seen again, presumably lost with all hands in the Bermuda Triangle.